Belt-tightener



(No Model.)

B. BENJAMIN. BELT TIGHTENER.

No. 403,454. Patented May 14, 1889.

I i i w NITED STATES PATENT OFFICE.

EDIVIN BENJAMIN, OF SOUTH EVANSTON, ILLINOIS, ASSIGNOR TO THE BEN- JAMIN MACHINE COMPANY, OF ILLINOIS.

BELT-TIGHTEN ER.

SPECIFICATION forming part of Letters Patent No. 403,454, dated May 14, 1889.

Application filed February 2, 1889. Serial No. 298,488. (No model.)

To all whom it may concern.-

Be it known that I, EDWIN BENJAMIN, of South Evanston, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Belt-Tighteners,

of which the following is a specification.

The object of my invention is to provide a belt-tightener applicable to the feed-works of wood-working machinery, by which the pressure of the tightener upon the belt can .be easily regulated to suit the work in progress, so that when narrow stuff is being worked and but little power is required for feeding, the pressure and wear upon the belts can be correspondingly diminished, and my object is further to provide for throwing the tightener into or out of action instantaneously and surely.

My invention consists in the parts and combinationshereinafter described and claimed.

In the accompanying drawings, Figure 1 is a side elevation of the bed of a planer having my improved belt-tightener attached, together with a portion of'the feed-pulleys sufficient to illustrate the invention. Fig. 2 is a similarview showing the tightener lifted from the belt. Fig. 3 is a plan view of the same parts. Fig. 4 is a section through line a; co, Fig. 2, looking from the left.

A is a pulley which drives the shaft B, the latter in turn driving the feed-gearing of any well known kind. The pulley A is driven by the belt O, the latter deriving its motion from any convenient source, as pulley D, upon a counter-shaft driven from the cylinder-driving devices. The belt O is loose upon the pulleys A and D, and the tightenerpulley E is brought into contact with said belt when it is desired to set the feeding mechanism in operation. The said tightener-pulley E is hung upon an arm, F, which turns on a stud or pivot, G, secured to the side of the bed. A counterbalance arm, H, projects on the opposite side of the supporting-stud G from the arm F, and a counterweight, I, is adjustably secured thereon. A projection or lug, J, of the arm F is provided with a series of holes, j, arranged in the arc of a circle whose center is the stud G. These 50 holes are adapted to receive a pin or stud, K,

upon which the connecting-rod L is pivoted. The other end of the connecting-rod L is pivoted at P to a hand-lever, M, the latter turning on a stud, N, secured to the side of the frame. A stop, 0, limits the motion of the hand-lever M when turned down.

The operation is obvious. IVhen the handlever M is turned up, as shown in Fig. 1', the tightener-pulley is allowed to drop upon the belt, and in this position would overbalance 6c the counter-Weight I. The position of the counter-weight I upon the arm H will determine the amount of pressure which the. tightener-pulley E exerts upon the belt C, so that only suffioient pressure need be used to feed the lumber; and in feeding narrow lumher the pressure necessary to maintain the feed willbe very slight, and the pressure upon the belt can be correspondingly reduced, The connection of the rod L to the arm F by means of a lug, J, bolt K, and a series of circumferentially-arranged holes,

j j, permits the tightener to be dropped lower as the belt becomes slacker without disturbing the position of the connecting-rod L or 7 5 the hand-lever M. By reason of the fact that both the tightener-pulley E and the counter-weight I are situated above the pivotal point G, the counter-weight I, when the tightener-pulley E is lifted from the belt, assumes a position in which it will nearly or quite overbalance the tightener-pulley, but all chance of its dropping upon the belt when not Wanted is prevented by the fact that the stop O does not arrest the hand-lever M until the pivot-points K, P, and N are brought into a straight line, and the gravity of the outer end of the hand-lever M is sufficient to maintain it in its depressed position, While the thrust resulting from the Weight of the tightener-pulley and its supporting-arm has no tendency to raise the hand-lever M.

I claim 1. The combination, in a belt-tightener, of a pivoted arm carrying the tightener-pulley and means for shifting said tightener, consisting of a hand-lever and a connecting-rod from said hand-lever, the latter connected to the tightener pulley arm by a stud adj ustable in a series of holes arranged circumfer= 10o entially with reference to the pivot of said reached a straight line joining the points K arm, as set forth. and N.

2. The combination of arm F, ti htenerpulley E, rod L, connected to the arrr l F and EDWIN BENJAMIN 5 lever M, the latter being pivoted to the frame, Witnesses:

and the stop 0, which arrests the movement J. I. VEEDER,

of the lever M after the pivotal point P has P. H. T. MASON. 

